Uses of isotopes in radioactive dating
One gram of of the element radium generates approximately 1 curie of activity (Marie Curie, the woman after whom the curie is named, did much of her research using radium).Food irradiation is a method of treating food in order to make it safer to eat and have a longer shelf life.Different isotopes tend to concentrate in particular organs: for example, iodine-131 settles in the thyroid gland and can reveal a variety of defects in thyroid functioning.Another isotope, carbon-14, is useful in studying abnormalities of metabolism that underlie diabetes, gout, anemia, and acromegaly.By comparison with the tree rings in the extremely old bristle-cone pines, however, a corrected carbon date can be found for objects over about 1500 years old.
(a) Iodine-131 with a half-life of 8.0 days and activity of 8 C may be taken as liquid or in a capsule.(b)Technetium-99 with a half-life of 6 hours gives gamma-rays of 140 ke V energy.(c) Iodine-123 is suitable for medical studies since it gives no beta- radiation.(d) Cobalt-60 sources of up to 10 000 curies have been used; such a source gives 200 R per minute at 1 m. The very long half-lives of these isotopes make them particularly suitable for finding the age of rocks.
When I think about the word 'radioactive', I think about a unique, unstable type of energy.
If an isotope has an unstable nucleus that breaks down to emit radiation, then these are what we call radioactive isotopes, also known as radioisotopes.
In this method, the activity of radioactive carbon ( carbon-14) present in bones, wood, or ash found in archaeological sites is measured.
Because the rate at which this activity decreases in time is known, the approximate age of the material can be...